Alice Moore, 23, left, and Tejas Dave, 23, right, talk to Kate Pernia as they canvass an Arlington neighborhood for Tom Perriello, who is running for the Democratic nomination for Virginia governor in Tuesday’s primary. (Matt McClain/The Washington Post)

Front doors swing open across Virginia’s picturesque Shenandoah Valley, and Jennifer Brown pops what should be an easy question: Do you plan to vote in the Republican primary for governor?

These are not just any front doors, but those belonging to reliable GOP primary voters, people fired up last year when Brown came ’round on behalf of Donald Trump.

But the response days before Tuesday’s gubernatorial primary is often a blank stare — something Democratic door-knockers are also seeing in abundance.

“A lot of people are just not even aware,” said Brown, a field director for Corey Stewart, the Prince William County Board chairman in a three-way contest with former Republican National Committee chief Ed Gillespie and state Sen. Frank W. Wagner (Virginia Beach). “They’re asleep at the wheel.”

On Tuesday, Virginians will pick one Republican and one Democrat to go head-to-head in November’s election for governor. The contest is shaping up to be the nation’s first competitive statewide race of the Trump era. But it’s more than that.

Meet the candidates running to become Virginia’s next governor

The outcome could point the way forward for two major political parties torn by populist ­establishment infighting. It will test whether the forces rocking Washington will consume state-level races. And it will show whether Democratic fury at Trump materializes at the polls — something that could turn the 2018 midterms into a wave election.

But first comes the primary. And canvassers for the three Republicans and two Democrats competing for the nominations are finding an electorate that seems largely tuned out.

“I tend to think the worst possible place for a candidate to become known is in the middle of the Donald Trump presidency,” said Stephen J. Farnsworth, a political scientist at the University of Mary Washington. “News out of Washington has become an extraordinary obsession these last six months, and that makes it virtually impossible even for candidates for governor to get all that much media and public attention.”

About a month before the primary, fewer than 2 in 10 Democratic-leaning and Republican-leaning voters said they were paying “very close” attention to the governor’s race, and a significant number were undecided, a Washington Post-Schar School poll found.

Shantanu Sharma, of Sterling, has been so upset by the drama on the other side of the Potomac — from “the latest FBI stuff” to the push to ease Dodd-Frank banking rules — that he phones the office of Rep. Barbara Comstock (R-Va.) every day.

“I let her know I’m watching,” said Sharma, 47, who works in software.

What he hasn’t been watching very closely is the Virginia governor’s race. Only recently did Sharma tear his gaze from Washington long enough to make a decision in the neck-and-neck Democratic contest between Lt. Gov. Ralph Northam and former congressman Tom Perriello.

“All these things at the national level have sucked all the local energy out of the room,” said Sharma, who after a little research settled on Northam.

The outcome of the Democratic contest will hinge on turnout, political strategists say. Northam would benefit from a smaller electorate made up of longtime party stalwarts, who skew older. A surge of young people and progressives inflamed against Trump could help Perriello. Both campaigns are chasing the African American vote, which could make up as much as 25 percent of the electorate.

The Democratic race probably will turn on the voter-rich Washington suburbs, where neither Northam nor Perriello has a natural base. Northam is from the Eastern Shore; Perriello is from Charlottesville.

As volunteers for those campaigns stormed Northern Virginia last weekend, they encountered some Democrats revved up by Trump. Frank Higgins, a 73-year-old retiree, assured the Northam volunteer on his Dumfries doorstep that he needed no prodding to vote.

“Anyone but Trump,” he said. “I don’t care what office it is.”

But even among fired-up Democrats, door-knockers found some who knew little about their choices for governor — or even that a primary was looming.

“I will admit I have been preoccupied with what’s going on in D.C., ” said Ambrea Watts, 33. “It’s surreal; I can’t believe what’s going on. Every day, it’s something else.”

Others were intentionally tuning out.

“When Trump won, I gave up watching,” said Julianna Senkiyre, 56, who was doing yardwork in Woodbridge when a teachers group came by for Northam.

Voter participation always drops sharply in Virginia’s off-year elections, especially for late-spring primaries. In 2008, nearly a million voters cast ballots in Virginia’s Democratic presidential primary. The next year, just 319,168 Democrats, or 6.3 percent of registered voters, turned out for the party’s hard-fought primary for governor.

This is the first time in Virginia history that both parties are holding contested primary elections for governor on the same day, said Geoffrey Skelley of the University of Virginia Center for Politics. (Some years, the parties opt for nominating conventions instead.) That could help boost turnout.

Skelley sees signs of life on the Democratic side, with requests for absentee ballots twice as high in that party’s primary as in the Republican contest. Voters have requested nearly as many absentee ballots for Tuesday’s Democratic primary as they did for their party’s March 2016 presidential primary — 26,783 this year compared with 28,412, according to the Virginia Public Access Project. Republicans have requested 13,882 ballots compared with 27,569 for the March 2016 presidential primary.

“That’s kind of amazing to me,” Skelley said. “Democratic interest seems to be higher at the moment.”

The lopsidedness could reflect the relative competitiveness of the Democratic contest: Polls show Northam and Perriello in a tight race while Gillespie has enjoyed a double-digit lead over Stewart and Wagner.

In the homestretch, the candidates are trying to stay visible and get their voters to the polls. Each campaign takes a different approach, depending on financial resources, political ties — and the personalities of the candidates.

The contrast is most stark among the Republicans. Gillespie, the well-funded former Washington lobbyist, political consultant and adviser to President George W. Bush, is tapping into $2.4 million in cash on hand to air TV ads statewide. And he spent $45,000 recently on microtargeting to squeeze the most Republican-leaning eyeballs out of every ad buy. He has eight paid field staffers.

Chris Pierson, 17, knocked on doors for Gillespie last weekend on leafy cul-de-sacs just north of Richmond but only hit houses that campaign data told him belonged to probable Republican voters. The high school junior was unfailingly polite and risk-averse — like Gillespie himself, who has opted out of some debates, favored controlled settings over public events and avoided weighing in on the Trump administration.

At their doorsteps, Pierson asked voters if they would consider Gillespie and handed them a palm card. He referred anyone with questions to the campaign website. When a woman told him she did not know who she would be voting for, he did not try to twist her arm.

“Okay, you can keep that [palm card], and I hope you have a great day, ma’am,” he said.

Pierson found a promising prospect a few doors down. John Sjostrom, 58, was working in his garage and said he had supported Gillespie in his unsuccessful bid to unseat Sen. Mark R. Warner (D) in 2014. And he blasted Stewart for building his bid around the preservation of the state’s Confederate monuments, which he thinks is a ridiculous distraction.

“Fix the potholes in Richmond, for God’s sake,” he said. “It’s a false issue.”

But when Sjostrom said he had to “check on a few things” before making his decision, Pierson did not inquire. There was no hard sell. He just offered a palm card and bid the voter a good day.

It has been a different story for the Stewart campaign. With $186,000 on hand as of June 1, it cannot afford much TV and has only a lean staff. Stewart was Trump’s Virginia campaign chairman for most of last year before he was ousted for being too outspoken even for that renegade outfit.

He has run as a provocateur, staging rallies for Confederate monuments, slamming Gillespie in harsh online ads and cheering Trump’s most controversial moves on Twitter — a cheap but attention-getting approach that has inspired passionate staffers like Heather Mitchell, his Northern Virginia regional director.

“I was at a McDonald’s the other day, and I saw a guy with a Trump sticker and a ‘deplorable’ sticker on his truck,” said Mitchell, who started talking to him about Stewart. “By the time I finished our conversation, I handed him a stack of palm cards and he was going to start handing them out to all of his friends and getting them to vote for Corey.”

Wagner, a veteran legislator and former shipyard owner with just $59,000 on hand, has struggled to get noticed. The former Navy diver did attract two TV crews last weekend, when he donned a wet suit and swam five miles of the Potomac River to draw attention to suicides among military veterans.

On the Democratic side, the financial picture is also lopsided — Northam had $1.3 million available as of June 1, while Perriello had $734,000 — but both have enough to air TV ads.

Both also have big-name backing. Northam has a lock on Virginia’s elected Democrats while Perriello has nationally prominent progressives.

Northam’s team can count on canvassers from the state’s gun control, abortion rights and gay rights groups as well as the state’s Democratic heavy hitters: on Saturday, Sen. Tim Kaine (D-Va.) gathered with Warner and Gov. Terry McAuliffe (D) to launch door-knockers for Northam across Northern Virginia.

Perriello has relied on more distant star power, rolling out a TV ad featuring Sen. Elizabeth Warren (D-Mass.), a leader of the party’s progressive wing. National progressive groups, including the Our Revolution group of Sen. Bernie Sanders (I-Vt.), have made calls for him. A phone bank is set to operate for him Sunday, at an activists’ gathering called the People’s Summit — in Chicago.

As all five campaigns make their final push, some see an opportunity in those blank stares.

“There are people who are saying ‘I don’t even know about the candidates,’ ” said Brown, Stewart’s Shenandoah Valley field director. “They can be persuaded. . . . You can rally some people into going and voting.”

Gregory S. Schneider contributed to this report.